JP3188289B2 - Seawater leak diagnostic equipment for plants - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for diagnosing seawater leakage in a plant, and more particularly, to a method for diagnosing seawater leakage in a piping system in a thermal power plant and automatically diagnosing a countermeasure for the detection. Related to the device.

[0002]

2. Description of the Related Art Conventionally, in a thermal power plant, steam is ejected from a turbine connected to a generator to rotate the turbine, and the steam that has completed the work of rotating the turbine is cooled, returned to water, and returned. The dewatered water is passed through an ion exchange resin to remove ionic substances and degassed.Clean water from which ionic substances and dissolved oxygen have been removed is heated again by a boiler to produce steam, and this steam is ejected to a turbine again. , Has a water circulation system. Here, the cooling of the steam is usually performed with seawater.

What is important in the water circulation system in such a thermal power plant is the management of the circulating water quality. That is, if the quality of the circulating water is poor, corrosion of the boiler, turbine, piping, and the like occurs, which causes a disadvantage that the life of the water circulation system is shortened.

In order to control the quality of water in a water circulating system in a conventional power plant, first, conductivity of water, pH of water, dissolved oxygen concentration in water, hydrazine concentration, dissolved hydrogen concentration in water, and total iron concentration in water. ,
Control of water turbidity, chlorine concentration in water, and sodium ion concentration in water can be mentioned.

[0005] Such water quality control is particularly necessary not only during operation of the thermal power plant, but also when the thermal power plant is once stopped and then restarted.
During the operation of the thermal power plant, if it is discovered that the quality of the circulating water has deteriorated, it is necessary to quickly pursue the cause of the quality deterioration of the circulating water in order to quickly prevent corrosion of piping and boilers, etc. When restarting the operation of the thermal power plant that was stopped, the water circulation system was replaced with normal circulating water, and the circulating system that may have been generated by the stagnant water remaining in the circulation system during the stoppage of the operation was considered. This is because it is necessary to quickly find the faulty part inside and repair it.

[0006] The conductivity of the water is managed to satisfy such a need, for example, to monitor the possibility of seawater used for cooling the steam entering the water circulation system. If seawater enters the circulating water, the concentration of ionic substances such as chloride ions should increase, and if the concentration of the ionic substances increases, the conductivity of the circulating water should increase. In addition, the pH of water described below
This is because ammonium ions can be detected in conjunction with the monitoring of.

The pH of the water is monitored by measuring the pH of the circulating water.
Monitoring the dissolved oxygen concentration in water is to prevent corrosion of piping, boilers or turbines, etc. The monitoring may be to monitor the presence of dissolved oxygen in the circulating water, such as by checking the degree of consumption of hydrazine added for deoxygenation from the circulating water. Monitoring the concentration of dissolved hydrogen in water can be used to diagnose abnormal conditions such as the occurrence of corrosion in turbines. Monitoring the total iron concentration in the water and the turbidity of the water can detect the presence or absence of scale. Monitoring of chlorine concentration in water and sodium ion concentration in water can check for contamination of seawater.

[0008] Such water quality management items are obtained by displaying data obtained by detectors and the like arranged at various points in the water circulation system on an instrument provided on a wall surface of a centralized monitoring device or the like and recording the data on a recording device. I was The observer discovered abnormal data from various types of detected data displayed on the instrument, comprehensively judged the various types of abnormal data, detected the cause of the abnormality, the location where the abnormality occurred, and took action. However, in such a monitoring method that relies on the experience of a supervisor, even if an abnormal state can be detected, it takes time to detect the location of the abnormality and to investigate the cause of the abnormality or to study the countermeasures. However, there is a problem that one has to rely on a skilled guard.

In such a thermal power plant,
The following measures have been taken to detect that the seawater for steam cooling has leaked into the water or steam piping system. That is, conventionally, a conductivity meter is disposed downstream of a condenser (a hot well, a condensate pump outlet, etc.), and the acid conductivity after passing through the cationic resin is measured by the conductivity meter to measure the thermal conductivity of the thermal power plant. By the process control of the above, the presence or absence of seawater leakage was comprehensively determined. Furthermore, finally, the chlorine ion concentration of the water flowing through the piping system was measured by hand analysis to ensure the accuracy of the determination of the presence or absence of seawater leakage. If seawater leakage occurs, the thermal power plant is carefully operated while checking the state of the desalination unit in the thermal power plant.

[0010]

However, the above-described conventional measures for preventing seawater leakage have the following various problems. That is, the measured value of the conductivity meter fluctuates greatly during cleanup at the time of starting the thermal power plant, so that only a limited number of experts can determine whether or not there is seawater leakage. In addition, the analysis of the chloride ion concentration of the water flowing through the piping system relies on manual analysis, and thus also has to rely on limited specialists. Further, the leakage of seawater to the piping system is not always constant over time, and therefore, there is a problem that the state of the desalination unit in the thermal power plant must be constantly monitored. The present invention has been completed based on the above circumstances. That is,
An object of the present invention is to provide a seawater leak diagnosis capable of automatically and always detecting and diagnosing seawater leak in a piping system in a thermal power plant.

[0011]

SUMMARY OF THE INVENTION The present invention for solving the above-mentioned problems is directed to a seawater leak diagnostic apparatus used in a thermal power plant using seawater for cooling a condensate system. Where the quality of the water is detected ,
Including conductivity meter, chlorine concentration meter and sodium ion concentration meter
And a non-water detecting means, determining means for determining seawater leakage based on the detection result of the detection target of the water quality detection means,
Based on each determination result of this determination means, regarding the state of leakage of seawater in the thermal power plant ,
Diagnostic processing means for diagnosing "suspicion of leakage" and "no leakage of seawater", and display means for displaying a comprehensive diagnosis result of the diagnostic processing means in different stages. It is a seawater leak diagnosis device of a plant.

[0012]

The operation of the above-described apparatus for diagnosing and diagnosing seawater leakage will now be described. The water quality detecting means in the seawater leak diagnosis / diagnosis device detects the water quality at a plurality of locations of the condensate piping, and sends each detection result to the determining means. The determination means determines the leakage of seawater based on the detection result of each detection target sent. The diagnosis processing means divides the comprehensive diagnosis of the state of leakage of seawater in the thermal power plant into three stages, for example, leakage, suspected leakage, and no leakage, based on each determination result of the determination means. Do it. The display means displays a comprehensive diagnosis result of the diagnosis processing means in different stages. As a result, the presence or absence of seawater leakage in the piping system can always and automatically be accurately grasped.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a thermal power plant including an apparatus according to an embodiment of the present invention will be described in detail.

FIG. 1 shows an outline of the thermal power plant.

(A) Water Circulation System in Thermal Power Plant-Configuration of Water Circulation System- As shown in FIG. 1, the condensing system condenses the steam after work in a cooling pipe ST that conducts seawater to form a liquid. A steam condenser C for converting into water, a condensed water storage tank HW ₁ , HW ₂ having a two-part configuration for storing condensed water, and a condensed water storage tank HW
₁ , Condensate pump CP for sending water discharged from HW ₂
The condensate desalination unit DEMI removes the ionic substances in the water sent by the condensate pump CP with ion exchange resin.
A condensate booster pump CBP for supplying water (desalinated water) from which ionic substances have been removed, a low-pressure heater LPHTR for heating the supplied water, and oxygen from the heated water heated by the low-pressure heater LPHTR. A degassing device DEA for removing
And a pipe for connecting these in series. Note that distilled water is supplied from the makeup water tank T to the condensed water storage tanks HW ₁ and HW ₂ through piping.

[0016] In this condensate system, first a valve V ₁ to the branch pipe branched from the pipe connecting the condensate pump CP and condensate demineralizer DEMI, condensate pump CP and condensate desalination A second valve V ₂ is provided on a side pipe that bypasses the condensate demineralization apparatus DEMI from a pipe connecting the apparatus DEMI, and a condensate booster pump CBP and a low-pressure heater LP.
Condensed water storage tanks HW ₁ , HW
Third valve V ₃ is provided on the side pipe back to _2, the deaerator D
Fourth valve V ₄ is provided in the pipe branched from the EA, the fifth valve V ₅ to the side tube back to the condensate storage tank HW _1, HW ₂ from the pipe coupling the deaerator DEA and the high-pressure heater HPHTR Is provided.

An ammonia injection pipe (not shown) for injecting ammonia into the water circulation system and a hydrazine injection for injecting hydrazine into the water circulation system are provided in a pipe connecting the condensate demineralizer DEMI and the condensate booster pump CBP. A tube (not shown) is connected. As shown in FIG. 2, the condensed water storage tanks HW ₁ and HW ₂ of the condensate system are connected to conductivity meters μS ₁ and μS ₂ for measuring the acid conductivity of water that has passed through a not-shown cationic resin. I have. The outlet of the condensate pump CP is connected to a chloride ion meter CL for measuring the chloride ion concentration in water and a conductivity meter μS ₃ for measuring the acid conductivity of water that has passed through a cation resin (not shown). Further, a sodium meter N for measuring sodium ion concentration in water is provided at the inlet of the condensate demineralizer DEMI.
A is connected.

The acid conductivity measured by the conductivity meter μS ₃ provided at the outlet of the condensate pump CP is corrected by a correction device. The correction device includes a makeup water flow meter (not shown) for measuring the flow rate of makeup water supplied from the makeup water tank T to the condensed water storage tanks HW ₁ and HW ₂ , a makeup water flow meter, and a conductivity meter. two A / D converters constituting the A / D converter 2 for digitizing the measurement data of μS _3, the data recording unit 4, the control operation means 13,
The diagnostic processing means 8 is formed. The diagnosis processing means 8 includes a dead time processing unit for processing a dead time (t) based on a difference in physical position between the flow meter and the conductivity meter μS ₃ , and the makeup water measured by the flow meter is used for storing condensed water. Tank HW ₁ , HW
A first-order lag processing unit that processes a first-order lag that occurs when flowing into ₂ , an arithmetic unit that includes a conversion processing unit that converts the make-up water flow rate subjected to the first-order lag process into acid conductivity, and the conductivity meter μS ₃ the AD converter, subtracts the calculation result of the arithmetic unit from the data a Sanshirube conductivity to take over the data recording unit 4 and the control operation unit 13, comprising a subtraction processing section for obtaining the correction Sanshirube conductivity a ₀ ing. The first-order lag processing unit in the calculation unit converts the measurement data C from the make-up water flow meter L from the make-up water tank T to the condensed water storage tank H.
After processing the first-order lag that occurs when flowing into W, the first-order lag is sent to the conversion processing unit, and the conversion processing unit converts the flow rate of the first-order lagged makeup water into acid conductivity.

The water supply system includes a high-pressure water supply pump BFP for generating high-pressure water by sending water discharged from the deaeration device DEA to a pipe narrowed to a small diameter, and a high-pressure water pump BFP sent from the high-pressure water supply pump BFP. -Pressure heater HPHTR for pre-heating water, and economizer ECO for pre-heating high-pressure water pre-heated by the high-pressure heater HPHTR to a higher temperature
And a water wall WW for converting high-pressure high-temperature water preheated to a high temperature by the economizer ECO to high-pressure steam, and high-pressure high-temperature water converted to steam by the water wall WW and high-pressure high-temperature water not converted to steam. And a water separator WS for separation.

This water supply system also includes a condensed water storage tank HW from a pipe connecting the economizer ECO and the high pressure heater HPTTR.
_1, HW to side tube ₂ Back to sixth valve V ₆ is attached, the seventh valve V ₇ is attached to the branch pipe branched from a pipe connecting the sixth valve V ₆ and the high-pressure heater HPHTR, Wota chromatography separator Condensed water storage tank H from WS
W _1, the eighth valve V ₈ on the side pipe back to the HW ₂ is attached, the ninth valve V ₉ is provided in the branch pipe branched from a pipe 8 connecting the valve V ₈ and Wota over wall WW.

The steam system includes a super heater S for further increasing the temperature of the high-pressure steam converted by the water wall WW.
P, a high-pressure turbine HP for injecting high-pressure steam raised to a high temperature by the super heater SP to drive the generator, and a reheater R for reheating the steam passing through the high-pressure turbine HP.
H, an intermediate-pressure turbine IP that ejects high-pressure steam reheated by the reheater RH to drive the generator, and an intermediate-pressure turbine I
And a low-pressure turbine LP that ejects high-pressure steam via the P to drive the generator.

-Movement of Water During Plant Operation in Water Circulation System-In the water circulation system configured as described above, water circulates during operation of the thermal power plant as follows.

That is, the steam that has completed the work in the low-pressure turbine LP is supplied to the steam condenser C, where the steam is cooled by the cooling pipe ST, condensed and converted into water as a liquid. The condensed water obtained by converting the steam into water is temporarily stored in the condensed water storage tanks HW ₁ and HW ₂ ,
Water is sent from the condensed water storage tanks HW ₁ and HW ₂ to the condensate demineralizer DEMI by the condensate pump CP. Condensate desalination equipment DE
The condensed water is ion-exchanged by the MI, and purified water from which ionic substances have been removed is sent to the low-pressure heater LPHTR by the condensing booster pump CBP. Low pressure heater LPHTR
, The purified water is preheated and sent to the deaerator DEA. In the deaerator DEA, purified water is deaerated, and mainly oxygen gas is removed.

The degassed purified water from which oxygen gas has been mainly removed is sent to the high pressure heater HPHTR as high pressure water by the high pressure water pump BFP. In the high-pressure heater HPHTR, the deaerated purified water is preheated. The preheated degassed purified water is preheated to a higher temperature in the economizer ECO.
The preheated high-pressure degassed purified water is converted into high-temperature and high-pressure steam in the water wall WW.

The high-temperature and high-pressure steam converted by the water wall WW is further heated to a high temperature by the super heater SP, and the obtained high-temperature and high-pressure steam is ejected to the high-pressure turbine HP, passes through the high-pressure turbine HP, and has a low temperature. The lowered high-pressure steam is heated again to a high temperature by the reheater RH, and thereafter supplied to the intermediate-pressure turbine IP to drive the intermediate-pressure turbine IP. The steam having passed through the intermediate pressure turbine IP is supplied to the low pressure turbine LP. The generator is driven by these high-pressure turbine HP, medium-pressure turbine IP, and low-pressure turbine LP, and outputs electric power. The steam that has passed through the low-pressure turbine LP is returned to the steam condenser C, and repeats the same cycle as described above.

-Water movement at start-up of thermal power plant-Thermal power plant performs periodic inspections,
When an abnormal condition occurs, the operation is stopped. While the operation is stopped, much circulating water still remains in the main piping of the water circulation system. The quality of the residual water deteriorates in accordance with the length of the shutdown period of the thermal power plant. Alternatively, dirt is generated in the piping. Therefore, when restarting the operation of the thermal power plant, it is necessary to clean the water circulation system.

The washing operation is performed as follows. That is, the addition to releasing the first valve V ₁ 2
The valve V ₂ and the inlet of the condensate demineralizer DEMI are closed, and make-up water is supplied from the make-up water tank T into the steam condenser C. The makeup water is supplied from the steam condenser C to the condensed water storage tank HW ₁ ,
It is stored in the HW _2. Then, by driving the condensate pump CP, discharged outside the makeup water from the first valve V _1. By discharging the make-up water supplied from the make-up water tank T via the steam condenser C, the condensed water storage tanks HW ₁ , HW ₂ and the condensate pump CP, from the first valve V ₁ to the outside of the system, steam condenser C, the condensed water storage tank HW _1, HW
_{2. The} condensate pumps CP and the piping connecting them are washed with makeup water.

After performing the above-mentioned cleaning operation for a certain period of time,
The thereby releasing the valve V ₂ and the third valve V ₃ 1
Closing the inlet valve V ₁ and the low-pressure heater LPHTR, condensed water storage tank HW _1, HW _2, condensate pump CP, the second side tube having a valve V _2, condensate booster pump CB
In circulatory system formed by the side tube having a P and a third valve V _3, circulating water. After circulating for a certain period of time, the inlet of the condensate demineralizer DEMI is opened and the second
The valve V ₂ is closed, and the condensed water storage tanks HW ₁ and HW ₂ , the condensate pump CP, the condensate desalination unit DEMI, the condensate booster pump CBP, and the circulation system formed by the side pipe having the third valve V _3. Circulate. At this time, the condensate desalination device D
The water circulated by EMI becomes desalinated water and will be washed.

Thereafter, by repeating the same operation,
Low pressure heater LPHTR, deaerator DEA, high pressure heater H
The PHTR, the economizer ECO, the water wall WW, the water separator WS, and the piping connecting them are cleaned.

(B) Water Quality Monitoring System The water quality in the water circulation system described above is monitored by a water quality monitoring system described below. Then, the monitoring result is displayed in real time.

FIG. 3 shows the configuration of the water quality monitoring system.

As shown in FIG. 3, the water quality monitoring system comprises a process signal generating means 1 in the water circulation system,
An AD converter 2 for converting a voltage value signal output from the process signal generating means 1 into a digital signal; and an electric conductivity installed in a water circulation system for detecting the quality of water and outputting it as voltage value data. ΜS ₁ , μS ₂ , μS,
Chloride ion meter CL, sodium meter NA and conductivity meter μ
Water quality detecting means 3 including S ₃ , AD converter 2 for converting voltage value data output from water quality detecting means 3 into a digital value, water quality detecting means 3 and process signal generating means 1 via AD converter 2 And a data recording unit 4 for converting the data from the data into engineering value data, and a graphic display of the water circulation system based on data output from the process signal generating means 1, the water quality detecting means 3 and the abnormal alarm generating means 7 which will be described later. A process state diagram creating means 5 for processing data such that water quality data and process data at each water quality detection site are collectively displayed, and the water circulation site in the water circulation system is displayed in, for example, light blue;
And the data output from the water quality detection means 3
Trend chart creating means 6 for processing the data so that the change of the designated water quality item is displayed as a graph in a time sequence.
And data output from the process signal generating means 1 and the water quality detecting means 3 so as to display the item of the abnormal water quality, the location of the occurrence, the date and time of occurrence, the content of the abnormality, etc. Inputting data output from the abnormality alarm generating means 7 for processing data, the process signal generating means 1 and the water quality detecting means 3 and inputting past water quality data from a first storage means 9 described later; Diagnostic processing means 8 for processing data so as to diagnose diagnostic information for assisting the operation of the thermal power plant and the cause of abnormal water quality and display the contents thereof; process signal generating means 1; and water quality detecting means. A first storage unit 9 for storing real-time data and past data output from the unit 3; a process state diagram creating unit 5; a trend diagram creating unit 6; A second storage means for storing each data output from the stage 7 and the diagnostic processing means 8 at an address corresponding to each pixel of the display screen divided into four parts, and a display means for reading out image data from the second storage means 12, a display driving means 11 and image data output from the display driving means 11 are input, and a water supply system, a steam system and a recovery system in the thermal power plant are Based on data output from the process state diagram and the trend diagram creating means 6 for displaying the water quality information on the current water quality in each part of the water circulation system in the water circulation system, the water quality related to the water quality history in each part of the circulation system is displayed. Based on the trend chart displaying the history information and the data output from the abnormal alarm generating means 7, the driving support information on the water quality and the diagnostic processing means 8 To diagnose the cause of the abnormal state when the data et output based on the measured quality on water quality management, a display unit 12 for displaying independently 4 area of the screen, the control arithmetic unit for controlling the respective means 13
And an input means 14 for instructing the control operation means 13 to operate or inputting predetermined data.

In this embodiment, the display means 1
2, a CRT screen is adopted, a process state is displayed in a substantially upper half area on the left side of the CRT screen, a trend diagram as water quality history information is displayed in a substantially upper half on the right side of the CRT screen, and a left side of the CRT screen is displayed. The diagnostic content as driving support information is displayed in a substantially lower half area, and the diagnostic content as water quality information is displayed in a substantially lower half area on the right side of the CRT screen.

-Each means in the water quality monitoring system-Each of the above-mentioned means will be described in further detail.

(A) Process signal generating means 1 The process signal generating means 1 includes a condensing system flow rate measuring device for measuring a water flow rate at an inlet of a condensing booster pump CBP in a water circulating system, and a water flow rate at an ECO inlet of a economizer. And a water supply flow rate measuring device for measuring the flow rate. The water flow rate measured by the condensing system flow measuring device and the water supply system flow measuring device is output to the AD converter as voltage value data.

(B) Water quality detection means 3 The items detected by the water quality detection means 3 include water conductivity, water pH, dissolved oxygen concentration in water, hydrazine concentration, dissolved hydrogen concentration in water, and total iron concentration in water. Turbidity, chlorine concentration in water, and sodium ion concentration in water.

The water quality detecting means 3 for measuring the electric conductivity of water includes:
It is a conductivity meter. By monitoring this conductivity, it is possible to check whether seawater, which is cooling water, has entered the circulation system, and to monitor the ammonia concentration in the water in the circulation system. In the water circulation system shown in FIG. 1, this conductivity is determined in the condensed water storage tanks HW ₁ and HW ₂ , the outlet of the condensate pump CP, the outlet of the condensate demineralizer DEMI, the inside of the low-pressure heater LPHTR, and the deaerator DEA. Inlet and deaerator DEA, high pressure heater HPTTR, economizer ECO
Of these, it is measured by a conductivity meter, which is one of the water quality detection means 3 provided from the outlet of the water separator WS or the like via a branch pipe. In this embodiment, only _three conductivity meters μS ₁ , μS ₂ and μS ₃ shown in FIG. 2 are shown.

The voltage value data on the water conductivity measured by the conductivity meter is outputted to the AD converter 2. The CRT screen on the display means 12 is displayed in MS or KMS.

The water quality detecting means 3 for measuring the pH of the water is p
It is an H meter. By monitoring this pH, the corrosion of iron can be monitored. This pH is determined by the outlet of the condensate pump CP, the outlet of the condensate booster pump CBP, the economizer EC
It is measured by a pH meter provided from an O inlet or the like via a branch pipe. In FIG. 1, the condensate booster pump C
Representatively, only the pH meter 22 provided at the outlet of the BP via a branch pipe is shown. The value of the pH of water measured with a pH meter is
The data is output to the AD converter 2 as voltage value data. The pH value is indicated by PH on the CRT screen of the display unit 12.

Here, the seawater leakage diagnosis apparatus of the present embodiment included in the water quality monitoring system will be described with reference to FIG. This seawater leak diagnostic device is provided with the three conductivity meters μ.
Water quality detecting means comprising S ₁ , μS ₂ , μS ₃ and a chloride ion meter CL, a sodium meter NA, and AD converters 2 a to 2.
2e, the data recording unit 4, the control operation unit 13, the diagnostic processing unit 8, the first storage unit 9, the second storage unit 10, and the alarm generation unit 7. And the display driving means 11 and the display means 1
2 is formed. Note that the conductivity meters μS ₁ and μS
_The error correction by the make-up water of the acid conductivity measured in ₂ is corrected by the conductivity correction device as described above. The seawater diagnostic processing means 8 includes the conductivity meter μS
₁ , μS ₂ , μS ₃ , a determination unit 21 for determining seawater leakage based on the measurement data of the chlorine ion meter CL and the sodium meter NA, and a determination unit 21 for determining the leakage of seawater. The apparatus further includes a comprehensive determination unit 22 that comprehensively determines a leakage of seawater, and a control unit 23 that controls these.

On the other hand, the water quality detecting means 3 for measuring the amount of dissolved oxygen in water is a dissolved oxygen meter. Monitoring the dissolved oxygen concentration can prevent corrosion in the circulation system. This is because the tendency of corrosion of iron to progress when the dissolved oxygen concentration increases is recognized. The dissolved oxygen concentration is determined by the outlet of the condensate pump CP, the inside of the low-pressure heater LPHTR, the deaerator DEA.
It is measured by a dissolved oxygen meter provided through a branch pipe from the inside and the deaerator DEA outlet, the high-pressure feed pump BFP outlet, the high-pressure heater HPHTR, the economizer ECO inlet, and the like. The dissolved oxygen concentration in the water measured by the dissolved oxygen meter is output to the AD converter 2 as voltage value data. In addition, on the CRT screen of the display means 12, the dissolved oxygen concentration is indicated by DO.

The water quality detecting means 3 for measuring the hydrazine concentration in water is a hydrazine concentration meter. Monitoring the concentration of hydrazine helps to monitor the dissolved oxygen concentration. Hydrazine is injected into the circulation to consume dissolved oxygen. This injection amount is determined so that a small amount of hydrazine remains in the economizer ECO. if,
If the amount of hydrazine injected is insufficient, the dissolved oxygen in the water cannot be completely removed, and if the dissolved oxygen is present as steam, for example, and injected into the turbine, the oxidation or corrosion of the turbine is promoted. This is because there is a disadvantage that the operable life of the power plant is shortened. Therefore, in a thermal power plant,
It is desirable to inject a predetermined amount of hydrazine into the pipe so that all of the hydrazine is consumed by dissolved oxygen before reaching the economizer ECO and a small amount of hydrazine remains in the economizer ECO. Therefore, the hydrazine concentration meter is provided via a branch pipe branched from an inlet of the deaerator DEA, an inlet of the economizer ECO, and the like. The hydrazine concentration measured by the hydrazine densitometer is output to the AD converter 2 as voltage value data. The hydrazine concentration on the CRT screen of the display means 12 is N2
Displayed in H4.

Water quality detecting means 3 for measuring the concentration of dissolved hydrogen
Is a dissolved hydrogen concentration meter. By monitoring the hydrogen concentration, the occurrence of an abnormal state in the turbine can be detected. The dissolved hydrogen concentration meter for measuring the concentration of dissolved hydrogen in water is provided in the reheater RH, the outlet of the intermediate pressure turbine IP, the economizer ECO, and the super heater SP. The concentration of dissolved hydrogen in the water measured by the dissolved hydrogen concentration meter is output to the AD converter 2 as voltage value data. The CRT on the display means 12
On the screen, the concentration of dissolved hydrogen is indicated by DH.

The water quality detecting means 3 for measuring the total iron concentration is a total iron analyzer. The measurement of the total iron concentration can monitor the generation of scale in the piping in combination with the turbidity of water described below. The total iron analyzer analyzes the iron ions in the water sampled from the condensate pump CP outlet, the inside of the low-pressure heater LPHTR, the economizer ECO, and the like in a batch process. For example, a total iron analyzer weighs sampled sample water in a sample measuring tank, guides this fixed amount of sample water to a heating tank, adds a thioglycolic acid solution, heats the solution, dissolves suspended iron, and prepares a second sample. After reducing the iron ions to ferrous ions, the solution was led to the reaction tank via a cooler. After adjusting the pH by adding an ammonium acetate buffer, the sample water colored by adding the TPTZ reagent was led to the measurement tank and the absorbance was measured. The measurement is performed, and the obtained measurement data is output to the AD converter 2 as voltage value data. The total iron concentration analyzed by the total iron analyzer is displayed in TFE on the CRT screen of the display means 12.

Incidentally, since the total iron concentration by the above-mentioned total iron analyzer is a batch process, the obtained data is discontinuous in time, and the data obtained by the above-mentioned turbidimeter is based on the principle of directly measuring the iron concentration. However, it is not possible to perform high-precision analysis because errors occur due to ionic iron present in water and variations in particle diameter.

In order to eliminate such inconvenience of the total iron analyzer and the turbidity meter, data of an arithmetic system described later is also adopted. That is, the data X from the turbidimeter is stored in the first storage means 9 continuously with time. The data output from the turbidity meter indicates the turbidity (transparency) of water in the water circulation system, and does not directly indicate the iron concentration. However, there is a correlation between the turbidity and the iron concentration obtained by manual analysis (manual analysis).

The first storage means 9 stores in advance a correlation function between the data of the turbidimeter and the data obtained by manual analysis of the iron concentration in water. This correlation function is, for example, the following linear regression line equation: Y = a + bX (where Y is data obtained by manual analysis [converted value of total iron concentration], X is data obtained by a turbidimeter, and a and b are water values in a power plant or the like). Is a coefficient that differs according to
According to this correlation function, the correlation between the output data from the turbidimeter and the data obtained by manual analysis of the iron concentration in water is at least about γ = 0.7. The data from the turbidimeter and the correlation function stored in the first storage means 9 are read out, and the control calculation means 13
This data is substituted into the correlation function to calculate the iron concentration conversion value L. The calculated iron concentration conversion value L is stored in the first storage means 9. The data Y output from the iron analyzer is also stored in the first storage means 9. This data Y indicates the iron concentration.

The control calculation means 13 synchronizes the output X of the turbidimeter continuously output with time and the output Y of the total iron analyzer. When both outputs are synchronized, the iron concentration conversion value L at the time of synchronization is read from the first storage means 9 and the iron concentration conversion value L is divided by the iron concentration conversion value Y obtained from the total iron analyzer to correct the iron concentration conversion value L. Calculate the factor Z. This correction factor Z is stored in the first storage means 9. This correction factor Z is stored in the first storage means 9 without being updated until the two outputs are next synchronized. In order to improve the accuracy of the corrected iron concentration, the correction factor Z calculated every time the two outputs are synchronized is stored in, for example, the first storage means 9 for three synchronizations, and the correction factor Z is corrected for three synchronizations. A weighted average or a weighted average of the factor Z is calculated by the control calculating means 13,
The obtained average correction factor Z may be stored in the first storage means 9. The control calculation means 13 reads the correction factor Z, multiplies the correction factor Z 'by the iron concentration conversion value L, and stores the iron concentration in the first storage means 9.

When the output data X from the turbidimeter and the output data Y from the total iron analyzer are not synchronized, the control operation means 13 immediately precedes the data stored in the first storage means 9. The correction factor Z 'or the average correction factor Z' obtained from the data at the time of synchronization is read out, and the correction factor Z 'is multiplied by the iron concentration conversion value L by the control calculation means 13 to obtain the obtained iron concentration. 1 storage means 9
To be stored.

The water quality detecting means 3 for measuring turbidity is a turbidity meter. By measuring the turbidity, the concentration of iron as a solid content in the circulating water can be measured, and the generation of scale in the piping can be monitored together with the total iron concentration. The turbidity meter is provided at the outlet of the condensate pump CP, the inside of the low-pressure heater LPHTR, and the branch pipe drawn from the economizer ECO or the like. As the turbidity meter, any of an absorption type and a scattered light type may be used. From this turbidity meter, the measurement data is output to the AD converter 2 as voltage value data. The turbidity analyzed by the turbidimeter is indicated by the display means 1
2 is displayed on the TV on the CRT screen.

Water quality detecting means 3 for measuring chlorine concentration in water
Is a chlorine concentration meter. By measuring the chlorine concentration, the contamination of seawater into the circulating water can be detected together with the detection of sodium ions described below. The chlorine concentration meter is provided at the end of the branch pipe drawn from the outlet of the condensate pump CP. The chlorine concentration in the water measured by the chlorine concentration meter is output to the AD converter 2 as voltage value data.

The water quality detecting means 3 for measuring the sodium concentration in water is a sodium ion concentration meter. The measurement of the sodium ion concentration can be used together with the measurement of the chlorine concentration to detect the intrusion of seawater into the circulating water.
The sodium ion concentration meter is provided at the end of the branch pipe drawn from the condensate demineralizer DEMI outlet. The sodium ion concentration in the water measured by the sodium ion concentration meter is output to the AD converter 2 as voltage value data.

(C) AD converter 2 The AD converter 2 converts the voltage value data, which is the process signal output from the process signal generating means 1, into digital data, and outputs the voltage output from the water quality detecting means 3. It converts analog data on various water qualities as value data into digital data. The AD converter 2 outputs the converted digital data to the data recording unit 4.

(D) Data Recording Unit 4 The data recording unit 4 converts the digital data output from the AD converter 2 into engineering value data, transfers it to the first storage means 9, and stores it.

(E) Process state diagram creating means 5 Process state diagram creating means 5
The water circulation system is graphically displayed in a predetermined area of the RT screen, for example, an upper left half area of the CRT screen, and the various water quality data detected by the water quality detection means 3 and the water in the water circulation system detected by the process signal generation means 1 are displayed. The necessary data is read from the first storage means 9 so that the flow rate can be displayed at regular intervals, graphic data for displaying the water circulation system as a simple graphic, and color display of the water circulation part in the water circulation system. The color display signal, the process data indicating the water flow rate in the water circulation system, and the water quality data indicating the water quality in each part in the water circulation system are output to the second storage means 10. Further, the process state diagram creating means 5 inputs the data on the water quality in the abnormal state output from the abnormality alarm generating means 7 and displays the display data for displaying the water quality in the abnormal state in red on the CRT screen in the second color. Output to storage means 10.

(F) Trend chart creating means 6 The trend chart creating means 6 uses the CRT
The specified area stored in the first storage means 9 is displayed in a predetermined area of the screen, for example, in the upper right half area, so that a change in the specified water quality over a certain period of time can be displayed on a graph with a vertical axis and a horizontal axis. The data regarding the water quality over a certain period is read out, the water quality is converted into graphic display data to be displayed in a graph figure, and this is output to the second storage means 10.

(G) Abnormal alarm generating means 7 This abnormal alarm generating means 7 is output from the water quality detecting means 3 and the process signal generating means 1 and is stored in the first storage means 9
Is read in real time and compared with a preset threshold value for each data. If the data read from the first storage means 9 exceeds the threshold value, data (abnormal data) exceeding the threshold value is detected. The date and time when the error occurred, the water quality item indicated by the abnormal data, the name of the department where the abnormal data occurred, and alarm information display data indicating the details of the abnormality are stored as water quality information. Further, the abnormal data is output to the process state diagram creating means 5, and
As described above, on the CRT screen, the water quality in the abnormal state in the process state diagram is highlighted in red.

(H) Diagnosis processing means 8 This diagnosis processing means 8 comprises the above-described three conductivity meters μS
₁ , μS ₂ , μS ₃ and seawater leak diagnosis based on data from the water quality detection means 3 composed of a chloride ion meter CL and a sodium meter NA, as well as a startup process water quality diagnosis, a chemical injection-related diagnosis, and an air leak determination auxiliary diagnosis. It has become. Next, the operation of the thermal power plant described above will be described mainly with reference to the operation of the seawater leakage diagnosis device and also with reference to FIGS. FIG. 5 is a flowchart of the seawater leak diagnosis, and FIG. 6 is a comprehensive diagnosis matrix table of the seawater leak diagnosis.

After the water quality monitoring system is activated, the conductivity meters μS ₁ , μS ₂ , μS ₃ , chlorine ion meter CL,
The sodium meter NA converts each measurement data into each AD converter 2a.
To 2e. Each of the AD converters 2a to 2e digitizes the measured data and sends it to the data recording unit 5. The data recording unit 5 converts each measurement data into engineering value data. Each of the engineering value data is sent to the determination unit 21 provided in the diagnosis processing unit 8 via the control calculation unit 13.

The acid conductivity measured by the conductivity meters μS ₁ and μS ₂ provided at the outlets of the condensed water storage tanks HW ₁ and HW ₂ is once corrected for error by the diagnostic processing means 8.
The corrected acid conductivity is used as data for seawater leak diagnosis. That is, the measurement data of the replenishment water flow meter (not shown) is digitized by the AD converter 2a, and then, via the data recording unit 4, via the control calculation means 13,
It is sent to a dead time processing unit (equipped in the diagnosis processing means 8; not shown) without the diagnosis processing means 10. The dead time processing unit obtains a dead time t based on a difference in physical position between the makeup water flow meter and the conductivity meter μS ₁ μS _2, and removes the measurement data c from which the dead time t has been removed. Means 8
Equipped inside. Not shown. ). The first-order lag processing unit processes the first-order lag that occurs when distilled water is supplied from the make-up water tank T to the condensed water storage tanks HW ₁ and HW _2, and then converts the measurement data c to the conversion processing unit (diagnosis processing). Means 8
Equipped inside. Not shown. ), The conversion processing unit converts the measurement data c in consideration of the first-order lag into an acid conductivity to obtain an error b, and subtracts the error b into a subtraction unit (diagnosis processing unit 8).
Equipped inside. Not shown. ). The subtraction means subtracts the error b from the measurement data a from the conductivity meters μS ₁ and μS ₂ (ab), and sends the subtraction result to the control calculation means 13 as a corrected acid conductivity a ₀ . The control calculation means 13 sends the corrected acid conductivity to the first storage means 9 and uses the corrected acid conductivity as data for seawater leak diagnosis in the diagnosis processing means 8.

On the other hand, as shown in FIG.
Are determined by the conductivity meters μS1, μS2, μ
Acid conductivity based on the measurement of S3 (conductivity meters μS1, μS2
Is exactly the corrected acid conductivity. ), Engineering value data of the chloride ion concentration measured by the chlorine ion meter CL, engineering value data of the sodium concentration measured by the sodium meter NA, and the first storage means 9.
Is compared with the existing data stored in the
, ΜS 2, chloride ion meter CL, and sodium meter NA, as shown in FIG. 6, three steps such as “leak”, “suspect of leak”, and “no leak” are performed.

The results of these determinations are taken into the overall determination section 22, and the overall determination section 22 makes the overall determination shown in FIG. 6 based on a matrix stored in advance. That is, for example, either the conductivity meter μS ₁ or μS ₂ leaks, the conductivity meter μS ₃ leaks, the chlorine ion meter C
When the overall judgment unit 22 takes in each judgment result of leak for L and leak for the sodium meter NA, the overall judgment unit 22 concludes that there is a leak as an overall judgment, and the control unit 23 The data is sent to the display means 12 via the display drive means 11. As a result,
On the screen of the display means 12, a message "leaving from seawater leaked from OO" is displayed, as exemplified in FIG.

Further, for example, there are no leaks for the conductivity meters μS ₁ and μS ₂ , no leak for the conductivity meter μS ₃ , no leak for the chlorine ion meter CL, and no leak for the sodium meter NA. When the general judgment section 22 takes in, the general judgment section 22
Concluded that there was no leak as a comprehensive judgment, and
3 is sent to the display means 12 via the control calculation means 13 and the display drive means 13. As a result, on the screen of the display means 12, a message indicating that "seawater has not leaked" is displayed as exemplified in FIG.

As described above, according to the seawater leak diagnostic apparatus, seawater to the water circulation system is measured based on the measurement data of the conductivity meters μS ₁ , μS ₂ , μS ₃ , the chloride ion meter CL, and the sodium meter NA. Detection and diagnosis of the presence or absence of leakage can always be performed automatically. The present invention, in addition to the embodiments described above,
Various modifications are possible within the scope of the gist.

[0065]

According to the present invention described in detail above, it is possible to provide a seawater leak diagnostic apparatus capable of always and automatically performing a comprehensive diagnosis of seawater leak to the piping system of a thermal power plant. .

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of a thermal power plant including an apparatus according to an embodiment of the present invention.

FIG. 2 is a schematic partial configuration diagram of a thermal power plant including the apparatus according to the embodiment of the present invention.

FIG. 3 is a block diagram of a water quality monitoring system in a thermal power plant including the apparatus according to the embodiment of the present invention.

FIG. 4 is a block diagram of an apparatus according to an embodiment of the present invention.

FIG. 5 is an explanatory diagram showing a diagnostic operation of the apparatus according to the embodiment of the present invention.

FIG. 6 is a list showing a comprehensive diagnosis matrix of seawater leak diagnosis of the apparatus according to the embodiment of the present invention.

[Explanation of symbols]

ST condenser C steam condenser HW condensation water tank CP condensate pump DEMI condensate demineralizer CBP condensate booster pump LPHTR low pressurizer DEA deaerator V ₁ first valve V ₂ second valve V ₃ third valve V ₄ fourth valve V ₅ fifth valve BFP pressure pump HPHTR pressure heater ECO economiser WW water wall WS water separator V ₆ sixth valve V ₇ seventh valve V ₈ 8 valve SP superheater HP high pressure turbine RH reheater IP medium-pressure turbine LP low-pressure turbine 1 process signal generating means 2 AD converter 3 water quality detecting means 4 data recording unit 5 process state diagram creating means 6 trend chart creating means 7 abnormality alarm generating means 8 diagnostic processing means 9 first storage means 10 Second storage means 11 Display drive means 12 Display means 13 Control calculation means 14 Input Means 21 Judgment Unit 22 Total Judgment Unit 23 Control Unit

Continued on the front page (72) Inventor Minoru Okada 3-2-2, Nakanoshima, Kita-ku, Osaka-shi, Osaka Inside Kansai Electric Power Company (72) Inventor Masanori Ota 3-2-2, Nakanoshima, Kita-ku, Osaka-shi, Osaka Inside Kansai Electric Power Co., Inc. (72) Inventor Masahiko Kurashina 3-43-2 Ebisu, Shibuya-ku, Tokyo Japan Machinery Co., Ltd. (72) Inventor Hisawazu Middle East 3-43-2 Ebisu, Shibuya-ku, Tokyo Japan Machine (72) Inventor Toshiaki Aoki 3-43-2 Ebisu, Shibuya-ku, Tokyo Nikkiso Co., Ltd. (56) References JP-A-61-256235 (JP, A) Japanese Utility Model Showa 55-77167 (JP, U) (58) Field surveyed (Int. Cl. ⁷ , DB name) G01M 3/00-3/40

Claims (1)

(57) [Claims] 1. A seawater leakage diagnosis apparatus for use in a thermal power plant using seawater for cooling the condensate system, where for detecting the water quality of water at a plurality of locations of piping condensate system
, Conductivity meter, chlorine meter and sodium ion meter
And water quality detection means including a determining means for determining the detection result based on sea water leakage into the in the detection target of the water quality detection unit, per leakage state of seawater in a thermal power plant based on each determination result of the determination means , "With seawater leak",
Diagnosis of "suspected seawater leak" and "no seawater leak"
An apparatus for diagnosing seawater leakage in a plant, comprising: diagnostic processing means for performing; and display means for displaying a comprehensive diagnostic result of the diagnostic processing means in different stages.